A novel Toll-like receptor 7/8-specific antagonist E6742 ameliorates clinically relevant disease parameters in murine models of lupus.

The sensing of self RNA by the endosomal Toll-like receptors (TLRs) 7 and 8 initiates pathogenic mechanisms underlying the autoimmune disease lupus. A blockade of the TLR7/8 signals may, therefore, be a novel therapeutic intervention for lupus. To test the hypothesis, a novel compound E6742 that blocks TLR7/8 activation was identified.

E6020, a TLR4 Agonist Adjuvant, Enhances Both Antibody Titers and Isotype Switching in Response to Immunization with Hapten-Protein Antigens and Is Diminished in Mice with TLR4 Signaling Insufficiency.

The mechanisms by which TLR4-based adjuvants enhance immunogenicity are not fully understood. We have taken advantage of a novel knock-in mouse strain that homozygously expresses two single-nucleotide polymorphisms (SNPs) that are homologous to human TLR4 (rs4986790 and rs4986791) and have been associated with LPS hyporesponsiveness in vivo and in vitro. TLR4-SNP (coexpressing mutations D298G/N397I in TLR4) mice that recapitulate the human phenotype were compared with wild-type (WT) mice for their hapten-specific Ab responses after immunization with hapten 4-hydroxy-3-nitrophenyl acetyl (NP) NP-Ficoll or NP-OVA in the absence or presence of a water-soluble TLR4 analog adjuvant, E6020.

Dissociation of TRIF bias and adjuvanticity.

Toll-like receptors (TLRs), a family of "pattern recognition receptors," bind microbial and host-derived molecules, leading to intracellular signaling and proinflammatory gene expression. TLR4 is unique in that ligand-mediated activation requires the co-receptor myeloid differentiation 2 (MD2) to initiate two signaling cascades: the MyD88-dependent pathway is initiated at the cell membrane, and elicits rapid MAP kinase and NF-κB activation, while the TIR-domain containing adaptor inducing interferon-β (TRIF)-dependent pathway is initiated from TLR4-containing endosomes and results in IRF3 activation. Previous studies associated inflammation with the MyD88 pathway and adjuvanticity with the TRIF pathway.

Preclinical efficacy of an anti-methamphetamine vaccine using E6020 adjuvant.

Background And Objective: Methamphetamine (MA) substance use disorder (SUD) does not have an efficacious pharmacotherapy. We developed a MA vaccine and investigated its potential to attenuate MA induced responses.

Methods: We examined a novel adjuvant, E6020, a Toll-like receptor-4 (TLR-4) agonist combined with tetanus-toxoid conjugated to succinyl-methamphetamine (TT-SMA) adsorbed on aluminum hydroxide (alum).

Building C(sp)-rich complexity by combining cycloaddition and C-C cross-coupling reactions.

Prized for their ability to rapidly generate chemical complexity by building new ring systems and stereocentres, cycloaddition reactions have featured in numerous total syntheses and are a key component in the education of chemistry students. Similarly, carbon-carbon (C-C) cross-coupling methods are integral to synthesis because of their programmability, modularity and reliability. Within the area of drug discovery, an overreliance on cross-coupling has led to a disproportionate representation of flat architectures that are rich in carbon atoms with orbitals hybridized in an sp manner.

Adults with autism spectrum disorder as behavior technicians for young children with autism: Outcomes of a behavioral skills training program.

Adults with autism spectrum disorder (ASD), who were interested in working as behavior technicians for young children with autism, participated in 2 experiments. Participants included 5 adults with Asperger syndrome or pervasive developmental disorder not otherwise specified, 19 to 23 years old, and 11 children with autism, 3 to 7 years old. In Experiment 1, training of the adults focused on the implementation of mand training via incidental teaching.

Design and preclinical characterization of a novel vaccine adjuvant formulation consisting of a synthetic TLR4 agonist in a thermoreversible squalene emulsion.

We describe the development, analytical characterization, stability and preclinical efficacy of AF04, a combination adjuvant comprising the synthetic toll-like receptor 4 (TLR4) agonist, E6020, formulated in AF03, a thermoreversible squalene emulsion. By using AF04 with the recombinant major outer membrane protein of Chlamydia trachomatis (Ct-MOMP) and with the recombinant surface glycoprotein gB from human cytomegalovirus (CMV-gB) as model antigens, we show that AF03 and E6020 can synergize to augment specific antibody and Th-1 cellular immune responses in mice. In terms of formulation, we observe that the method used to incorporate E6020 into AF03 affects its partition between the oil and water phases of the emulsion which in turn has a significant impact on the tolerability (IV pyrogenicity test in rabbits) of this novel adjuvant combination.

Training adults with an autism spectrum disorder to conduct discrete-trial training for young children with autism: a pilot study.

We evaluated a behavioral skills training program for adults with autism spectrum disorder and mild or no intellectual disabilities who were interested in learning the skills used by behavior therapists to work with young children with autism and other developmental disabilities. Four adults, aged 21 to 30 years, participated. We trained each individually using verbal and written instructions, modeling, and role play with feedback to teach 2 basic skills to an adult who played the role of a young child with autism.

Respiratory syncytial virus fusion protein-induced toll-like receptor 4 (TLR4) signaling is inhibited by the TLR4 antagonists Rhodobacter sphaeroides lipopolysaccharide and eritoran (E5564) and requires direct interaction with MD-2.

Unlabelled: Respiratory syncytial virus (RSV) is a leading cause of infant mortality worldwide. Toll-like receptor 4 (TLR4), a signaling receptor for structurally diverse microbe-associated molecular patterns, is activated by the RSV fusion (F) protein and by bacterial lipopolysaccharide (LPS) in a CD14-dependent manner. TLR4 signaling by LPS also requires the presence of an additional protein, MD-2.

MF59 oil-in-water emulsion in combination with a synthetic TLR4 agonist (E6020) is a potent adjuvant for a combination Meningococcus vaccine.

The inclusion of a potent TLR4 immune potentiator to a recombinant antigen vaccine formulation enhances both the magnitude and the breadth of the engendered immune response. One such immune potentiator (TLR4 agonist E6020) was evaluated with recombinant Men B antigens delivered in MF59 sub-micron adjuvant emulsion. The ability of this formulation to enhance serum antibody and bactercidal titers was investigated.

Effective antibody therapy induces host-protective antitumor immunity that is augmented by TLR4 agonist treatment.

Toll-like receptors are potent activators of the innate immune system and generate signals leading to the initiation of the adaptive immune response that can be utilized for therapeutic purposes. We tested the hypothesis that combined treatment with a Toll-like receptor agonist and an antitumor monoclonal antibody is effective and induces host-protective antitumor immunity. C57BL/6 human mutated HER2 (hmHER2) transgenic mice that constitutively express kinase-deficient human HER2 under control of the CMV promoter were established.

MF59 emulsion is an effective delivery system for a synthetic TLR4 agonist (E6020).

Purpose: The effectiveness of vaccines depends on the age and immunocompetence of the vaccinee. Conventional non-adjuvanted influenza vaccines are suboptimal in the elderly and vaccines with improved ability to prevent influenza are required. The TLR4 agonist E6020, either given alone or co-delivered with MF59, was evaluated and compared to MF59 and the TLR9 agonist CpG.

Hemoglobin enhances the biological activity of synthetic and natural bacterial (endotoxic) virulence factors: a general principle.

Although hemoglobin (Hb) is mainly present in the cytoplasm of erythrocytes (red blood cells), lower concentrations of pure, cell-free Hb are released permanently into the circulation due to an inherent intravascular hemolytic disruption of erythrocytes. Previously it was shown that the interaction of Hb with bacterial endotoxins (lipopolysaccharides, LPS) results in a significant increase of the biological activity of LPS. There is clear evidence that the enhancement of the biological activity of LPS by Hb is connected with a disaggregation of LPS.

E6020: a synthetic Toll-like receptor 4 agonist as a vaccine adjuvant.

Safe and cost-effective adjuvants are a critical component to enhance the efficacy of subunit vaccines. Studies have demonstrated that modified natural lipid As derived from enterobacterial lipopolysaccharides, which are agonists of Toll-like receptor 4, are beneficial to vaccine performance. The synthetic phospholipid dimer, E6020, mimics the physicochemical and biological properties of many of the natural lipid As derived from gram-negative bacteria.

Synthetic Toll-like receptor 4 agonist enhances vaccine efficacy in an experimental model of toxic shock syndrome.

The development of new protein subunit vaccines has stimulated the search for improved adjuvants to replace traditional aluminum-containing products. We investigated the adjuvant effects of a synthetic Toll-like receptor 4 (TLR4) agonist on vaccine efficacy in an experimental model of toxic shock syndrome. The TLR4 agonist E6020 has a simplified structure consisting of a hexa-acylated acyclic backbone.

Toll-like receptor 2 antagonists. Part 1: preliminary SAR investigation of novel synthetic phospholipids.

Novel synthetic phospholipid compound 1 was discovered to be an antagonist of human toll-like receptor 2 (TLR2) signaling. In a preliminary SAR campaign we synthesized several analogues of 1 and found that considerable structural changes could be made without loss of TLR2 antagonistic activity.

The induction of super-resistance using synthetic lipopolysaccharide receptor agonist rescues fatal endotoxemia in rats without excessive immunosuppression.

Endotoxin tolerance provides protection against mortality under various conditions of stress. However, the induction of endotoxin tolerance thus far has no clinical application because of endotoxin toxicity and the excessive immune suppression that follows the tolerance induction. In this study, we examined whether a novel, synthetic lipopolysaccharide (LPS) receptor agonist, ER-803058 (ER) can induce endotoxin tolerance with accompanying low toxicity.

Structurally simplified macrolactone analogues of halichondrin B.

A structurally simplified macrolactone analogue of halichondrin B was identified that retains the potent cell growth inhibitory activity of the natural product in vitro.

Inhibition of endotoxin response by synthetic TLR4 antagonists.

Endotoxin, from the outer membrane of Gram-negative bacteria, has been implicated as the etiological agent of a variety of pathologies ranging from relatively mild (fever) to lethal (septic shock, organ failure, and death). While endotoxin (also known as lipopolysaccharide or LPS) is a complex heterogeneous molecule, the toxic portion of LPS (the lipid A portion) is relatively similar across a wide variety of pathogenic strains of bacteria, making this molecule an attractive target for the development of an LPS antagonist. Research over the past fifteen years focused on the design of various lipid A analogs including monosaccharide, acyclic and disaccharide compounds has lead to the development of E5564, an advanced, unique and highly potent LPS antagonist.

Association of the endotoxin antagonist E5564 with high-density lipoproteins in vitro: dependence on low-density and triglyceride-rich lipoprotein concentrations.

The objective of this study was to determine the distribution profile of the novel endotoxin antagonist E5564 in plasma obtained from fasted human subjects with various lipid concentrations. Radiolabeled E5564 at 1 microM was incubated in fasted plasma from seven human subjects with various total cholesterol (TC) and triglyceride (TG) concentrations for 0.5 to 6 h at 37 degrees C.

The generalized endotoxic principle.

Bacterial lipopolysaccharides (endotoxins, LPS) belong to the most potent immunostimulators in mammals. The endotoxic principle of LPS is located in its lipid A moiety, which for Escherichia coli-type LPS consists of a hexaacylated diphosphoryl diglucosamine backbone. This lipid A adopts a cubic inverted aggregate structure from which a conical shape of the molecule can be deduced, whereas the tetraacyl lipid A precursor IVa adopts a cylindrical shape and is endotoxically inactive, but antagonizes active LPS.

Novel synthetic LPS receptor agonists boost systemic and mucosal antibody responses in mice.

Safe and cost-effective adjuvants are a critical requirement for subunit vaccine development. We report here the in vivo activity of a series of fully synthetic LPS receptor agonists that have been shown to activate NF-kappaB signaling through the Toll-like receptor 4 (TLR4). These compounds boost antibody responses to protein antigens when coadministered at microgram doses in mice.

A novel class of endotoxin receptor agonists with simplified structure, toll-like receptor 4-dependent immunostimulatory action, and adjuvant activity.

A series of novel, synthetic compounds containing lipids linked to a phosphate-containing acyclic backbone are shown to have similar biological properties to lipopolysaccharide (LPS). These compounds showed intrinsic agonistic properties when tested for their ability to stimulate tumor necrosis factor-alpha in human whole blood and interleukin-6 in U373 human glioblastoma cells without added LPS coreceptor CD14. The presence of the LPS antagonist E5564 completely blocked responses, suggesting that the novel compounds and LPS share a common mechanism of cell activation.